Mathematicians discover the nature of mathematics despite what they want. What I mean by that is something like the following. It was a great shock to mathematicians when they discovered that the square root of two is irrational. That's not something that they wanted. The number pi is irrational. That's also not something mathematicians wanted. What I'm pointing out here is that mathematics exists and is discovered. It's not invented by humans. It's something which is discovered. Therefore, in some sense, it exists in order to be discovered.

The view on ethics I take as an ethical realist is it's the same, the nature is sitting there in some sense waiting to be discovered. And the deep nature of ethics...is what we call kenotic ethics.

[Kenosis is] a Greek word meaning letting go or giving up, and it's used in the Bible in Philippians. It's central to my understanding of Christianity, and there's a spectrum which goes through in practical terms from forgiveness, which is a crucial part in which you are giving up the need for revenge. And it goes through to self-sacrifice on behalf of others, which is what Gandhi was about, Martin Luther King was about. And to me, that's the really, really deep transformative principle, which was also in the life of Christ, of course, when he sacrificed himself on behalf of others.

I think it's important to say that to me, kenosis is a generic principle which is much wider than just ethics. For instance, it's actually central — this emptying oneself — it's actually central to education and learning, because if you go into learning any subject with a preconceived notion, you can't learn. You have to empty your mind of your preconceived notion that you can see something new.

In ethics, though the key point about kenosis is the willingness to give up, which makes way for contact with the human part of the other person. And it's a kind of moral jujitsu in that they're expecting you to react in the way that they want you to react. They are your enemy and they want you to be their enemy. And if you refuse to be their enemy, then they don't know how to handle it.